4. OBJECTIVES
• Define pollination.
• Define fertilization and state its function.
• Describe and draw the stages of fertilization beginning with the arrival of the pollen
grains at the stigma to the fusion of male cell with the female cell in the ovary.
• Apply the concept of pollination and fertilization to solve scenarios involving a
defect in the pollination process or fertilization process or parts of the flowering plant.
Generate a possible explanation on how the defect affects the entire pollination or
fertilization process and sexual reproduction of flowering plants.
5. REPRODUCTION OF LIVING THINGS
• Humans and mammals give birth to young, birds and amphibians lay eggs.
• How do stationary living things like flowers reproduce?
• With the help of our mobile friends, the pollinators!
7. IMPORTANCE OF POLLINATORS
Image 1. Bee rubbing its hairy body against the filaments. Image 2. Bee carrying thousands of pollen grains on its hairs.
8. POLLINATION & FERTILIZATION
PROCESS OVERVIEW
Pollination is the process by which pollen grains
are transferred from the anther to the stigma.
Fertilization is the fusion of the male sex cell (in
the pollen grain) and the female sex cell (in the
ovule).
Function of fertilisation: For sexual reproduction
9. POLLINATION PROCESS
1. Pollen grains from another anther is transferred onto the stigma of the
recipient flower as pollinators gather nectar for food.
11. FERTILIZATION PROCESS
2. Once conditions are right, pollen tubes from the pollen grains will start to
grow into the style.
This will create a pathway for the pollen grain to travel down to the ovary.
12. FERTILIZATION PROCESS
3. Once the pollen grain reaches the ovary, the male sex cell inside the pollen
grain fuses with the female sex cell inside the ovule.
Recap on last lesson where they learn parts of the flower and the different types of pollinators. They have only been taught who the pollinators are without explaining what they do in relation to flowers.
Link reproduction in flowering plants with pollinators and how they need each other
Show video first. When the bees (pollinators) search for food (honey in flowers), they use their tongue to reach for honey deep inside the flower. Sometimes the flower is too deep and their tongue is not long enough. Hence they have to fly inside the flower. When they enter the flower, they rub their body against filaments of the flower which then sticks onto their hairy body. When the bee flies to another flower to search for more food, it brings along the pollen from the previous flower. As the bee repeat the whole process again, the pollen gets transferred to the stigma of the recipient (2nd) flower. As a result, the recipient flower is pollinated.
Pollinators gather nectar for food. As pollinators move from one flower to another to gather more nectar, the pollen grains on the pollinator’s body gets transferred to the stigma of the recipient flower.
